Mobians and Equestria Girls: Rainbow Rocks
by Darkmaster0224
Summary: Following the events of the the M&EG: Fates Between Worlds, the Mobians had returned to the Mobian dimension, leaving the human world of Canterlot High back to its original peace. Or so they thought. But what happens when three mystical and musical creatures from Equestria obtain Chaotic Equestrian magic? Heroes must return and join together once again to save the world AGAIN.
1. Chapter 1

**Darkmaster0224:** EYO EVERYONE! Its Darkmaster0224! I'm here to bring you yet another crossover story! This one is for the fans who wanted it. But people requested I remake Rainbow Rocks and the Friendship Games with the Mobians and Equestria Girls timeline. So this one will be obviously Rainbow Rocks first! This might change the Mobians and Equestria Girls original timeline slightly, so it won't actually be followed by Mobians and Equestria Girls 2. But I've got like 20 requests to remake it, so I will try my best. This will technically just be a spinoff, or an alternate story timeline breaking off from the original, ok? This won't be as good as the original series, but hopefully it will do.

But before we even start, let's welcome back CosmicAlchemist!

 **CosmicAlchemist:** Hey what's up everyone, I just want to say it's great to be back!

 **Darkmaster0224:** So, let's get this party started!

 **Disclaimer:** I do NOT own anything from Rainbow Rocks or My Little Pony FIM/EG (as much as I wish I did) they belong to Hasbro. I also don't own any of the Sonic characters, those belong to Sega. I own only the OCs.

Following the events of the the Mobians and Equestria Girls: Fates Between Worlds, the Mobians had returned to the Mobian dimension, leaving the human world of Canterlot High back to its original peace. Or so they thought. But what happens when three mystical and musical creatures from Equestria obtain Chaos energy and Equestrian magic? And plan to use it to conquer the world? Heroes must return and join together once again to save the world _again_ , while surviving highschool, _AGAIN_.

 **Notice to Sonic3461 (if you read this):** I'm not going to use Ace in this story. Only a mention or two of him.

 **Chapter 1**

 **Welcome to Canterlot High**

 **(Minutes before the Battle)**

In the dark streets of Canterlot City, people were in panic.

Dark Mephiles, Metal Overlord, and Nightmare Rose had taken over the city, turning it inside out.

However, three figures weren't in a panic of shock, but in awe.

"Who could have done this?" Adagio Dazzle said looking around at the havoc.

"Whoever it was, they sure must have a lot of power." Aria Blaze said.

"So much destruction. We need power like that!" Sonata Dusk squealed.

Aria rolled her eyes, "Do you ever stop being cheery?"

"Well maybe you should be more cheery." Sonata replied.

"Uhg. Enough with the arguing you two!" Adagio shouted.

Suddenly the three sirens felt a sudden energy pulse both familiar and not. It was Equestrian Magic, but more Chaotic than usual.

"Did anyone else just feel that?" Adagio said looking at her pendant shine.

"Yeah. It was Equestrian Magic." Sonata said.

"But it felt… different." Aria said.

"More… Chaotic." Adagio said smirking, "We need to find this new Equestrian Magic and make it ours."

"But we don't even know where to look." Aria pointed out.

Adagio was going to say something, but an explosion interrupted her.

They turned and saw Metal Overlord fly high into the sky, followed by three golden figures. All three were teenagers.

"Something tells me the magic is somewhere in a high school." Sonata said, "I mean those guys looked to be teenagers."

"No really? We didn't notice." Aria said glowering at Sonata.

"Really? I thought it was obvious." Sonata said tilting her head.

Adagio and Aria facepalmed.

"Idiot." Aria mumbled.

"Well girls, looks like we're going to highschool." Adagio said.

"Yay!" Sonata squealed jumping up and down.

"Great." Aria groaned.

 **(A year later)**

 **(Equestria Girls' POV)**

"WOHOOO!" Rainbow Dash shouted pumping her fist into the air, "I can't want for this year! It gonna be so much fun!"

"I'm just hoping for a normal school year. No magic, no visitors from another dimension, and no crazy monsters trying to take over the world." Applejack said, then realized what she said and looked at Sunset Shimmer, "Uh, no offence Sunset."

Sunset chuckled, "None taken, AJ."

"Here here, I've had simply enough magic and fighting for once." Rarity said, "It's by far too much for my wardrobe."

"I kind of wanted a reason to use our new powers. It's been so boring since the battle last year." Rainbow said looking at her chaos bracelet.

"You're still wearing that?" Sunset asked, "I took mine off the moment I got home. I personally don't ever want to use it again. It changed who I was." She said shivering, "I took someone's life with the sword I used. Another demon haunting me."

Applejack put a hand on her shoulder, "You did what you had to do."

"I use mine all the time!" Pinkie shouted jumping up and down, "Party Cannons on my arms! So much fun!"

When the girls got to the school, they heard Principal Celestia's voice over the loudspeaker, "Welcome students, new and old, to Canterlot High School!"

Several students cheered loudly.

"Now, I have a few announcements to make. Firstly, we have an exciting new fundraising event coming up for this year. A musical showcase!" Celestia announced.

Excited gasped were heard all around.

"Secondly, due to last year's um… incident, we've had to take extra security precautions." Celestia said.

The girls looked confused, but then they saw there were police officers around the area also.

"A little overkill don't you think?" Sunset asked.

"And lastly, I would like to see the following students in my office before classes start." Celestia said, "Rainbow Dash, Applejack, Sunset Shimmer, Rarity, Fluttershy, and Pinkie Pie."

"Go figure. Should have known she'd want to see us." Rainbow said walking into the school.

"Well of course. We're the ones full of all sorts of magic and what nots." Sunset said following her friends.

None of the girls noticed the three new students in the back of the crowd of students.

"Ok. So we've applied into the school. This is not only an opportunity for us to gain the Equestrian Magic, but to feed off the other students here also." Adagio said.

"And eat tacos too!" Sonata said.

"What?" Adagio asked turning to the light blue siren.

"Eat tacos. Tacos are for lunch on Tuesdays." Sonata said.

Aria rolled her eyes, "You know you're an idiot, right?"

"No you are." Sonata said in response.

"Oh my god, SHUT UP!" Adagio shouted.

Students turned at the shout, looking at the three.

"You three are so annoying. Can't you ever not argue!" Adagio shouted at the two.

Aria and Sonata saw the students staring.

"Um, Dagi, you have an audience." Sonata said pointing at the students behind Adagio.

Adagio turned and saw the students, "What are you all looking at?"

They all turned and quickly walked into the school.

The three sirens followed them from a distance.

"We just need to act like normal students, until the time is right to strike." Adagio said.

"Hello. Are you the new students?" A voice asked as the three walked in.

They looked in front of them and saw Vice Principal Luna.

"We are." Adagio replied.

"It is nice to meet you. I am Vice Principal Luna." Luna said, "We will have a student come to show you around in a few minutes. Here are your schedules." She handed them each a small paper with their classes on them, "If you are in need of anything, just let me or my sister know." Then she walked off.

The three looked at their schedules, and smirked, "All our classes are together. Good. Easier to subject victims."

 **(Celestia's Office)**

"So for this year, I would like to minimize the use of magic as much as possible." Celestia explained to the girls, "The other cities are unaware of the city's magic. As far as they are aware, it was a terrorist attack. Covered up by the government."

"Seriously? No magic? Aw come on." Rainbow groaned.

"I'm set with that." Applejack said, "A normal school year would be good."

"One more thing. We're not expecting any _visitors_ , are we?" Celestia asked, punctuating visitors.

"As far as we are aware, no one else will be coming by." Sunset said, "Twilight is probably busy, and the others have no way back anyways."

"Ok. That's all I needed all you for." Celestia said, "Oh, but I needed Sunset for something."

The others looked at Sunset, then nodded and left.

"What is it you need me for?" Sunset asked.

"We have three new transfer students this year." Celestia said, "I would like you to show them around. But try to keep the magic mentions to a minimum."

"You want _me_ to show them around? Why me?" Sunset asked.

"Because I trust you, Sunset." Celestia said placing her hand on Sunset's shoulder.

Sunset smiled and nodded, "I won't let you down."

"I know you won't." Celestia said watching the fiery girl leave.

 **(Front Entrance)**

Sunset walked to the front entrance of the school and saw three girls in the shadows, "Hi. Are you the girls I'm supposed to show around?"

"We are." Adagio said as the three sirens stepped out of the shadows.

 **Darkmaster0224:** And there you have it, chapter 1. Take it away bro!

 **CosmicAlchemist:** So, now the girls have both Equestrian and Chaos energy within them, but this has attracted the attention of the three legendary Sirens. Now they are in High School with them, and are planning on taking their magic for themselves. What will happen to them? What's the Musical Showcase gonna be like? Find out next time!

 **Both:** On Mobians and Equestria Girls: Rainbow Rocks! PEACEOUT!


	2. Chapter 2

**Darkmaster0224:** Howdy do buckaroos?! Darkmaster0224 here, bringing you another chapter to Mobians and Equestria Girls: Rainbow Rocks!

 **CosmicAlchemist:** Last time: The equestria girls have both Equestrian and Chaos energy within them, but this has attracted the attention of the three legendary Sirens. Now they are in High School with the girls, and are planning on taking their magic for themselves. When will the girls realise what the three new girls are?

 **Chapter 2**

 **Chaos Harmony Returns**

 **(Canterlot High)**

As Sunset was bring the three new girls around, she noticed the poster for the Musical Showcase. She smiled and ran over to it, "Oh, we're having a musical showcase next week. I'm sure if you spoke to principal Celestia, she'd would surely let you sign up."

"A _musical_ showcase you say?" Adagio said looking at her sisters.

"We do happen to sing from time to time." Aria said.

"Duh, we sing like all the time." Sonata blurted.

Adagio whipped around and signaled for her to shut up.

"What did I say?" Sonata asked confused.

"What you _meant_ to say is that this showcase is a great way for us to meet other students." Adagio said glaring at the youngest sister.

"Oooh. Right. What she said I meant to say. That's what I meant to say." Sonata said.

"What you meant to say, if you weren't the _worst_!" Aria said.

"No you are." Sonata replied.

"You'll have to excuse them." Adagio said standing in front of the arguing sisters, "They're idiots."

There was an awkward moment of silence, then Sunset saw their matching pendants, "Oh. Those are pretty."

Adagio made a quick swipe at Sunset's wrist, then realized what she was doing, "Ahehehe. Sorry, these pendants mean an awful lot to us. We'd just hate to see anything happen to them."

The three went on past Sunset, Aria needing to pull Sonata to follow them.

Sunset looked at the three in question.

 **(Outside the School)**

Seven shiny object were falling from the sky, each with a separate crash course.

One crashed into the school front lawn. It was a glowing red emerald.

The other six stopped in mid air above the school, and then flew off towards the city.

The red chaos emerald glowed brightly, waiting for someone to pick it up. Inside the Chaos Emerald, a red lightning bolt crystal object glowed.

 **(School Cafeteria)**

Sunset sighed as she sat down next to her friends, not even going to get her lunch.

"So how was the tour?" Applejack asked.

"I don't know, those girls… There's something, off, about them." Sunset said.

"Oh oh oh, you mean off like this?" Pinkie said fumbling her hair, "Or off like this?" She put her carrots in her mouth making her look like a vampire, "Or or!"

"How about we just let her explain." Rainbow said.

"That's just it, I can't seem to understand." Sunset said.

Speaking of which. The Dazzlings came into the cafeteria, singing in a lovely tone.

Everyone's attention went to the three girls.

They began singing, "Aah ah ah, aah ah ah. Aah, ah, ah."

" _We heard you want to get together._

 _We heard you want to rock the school_

 _We thought of something that is better_

 _Something that changes all the rules_

 _Why pretend we're all the same_

 _When some of us shine brighter?_

 _Shine brighter_

 _Here's a chance to find your flame_

 _Are you a loser or a fighter?_

"What the heck is this all about?" Rainbow asked.

"I don't know. The musical showcase isn't starting until next week." Applejack said.

"Maybe they're just trying to show off." Sunset said, 'Or maybe there is something else going on.' She thought looking at their glowing pendants. She didn't remember them glowing before.

 _Me and you, you and me_

 _Why don't we see who is better?_

 _We don't have to be one and the same thing_

 _Oh, what's so wrong with a little competition?_

 _Are you afraid of failing the audition?_

 _You're a star and you should know it_

 _Yeah, you rise above the rest_

 _It doesn't matter who you hurt_

 _If you're just proving you're the best_

 _Ah, ahh-ahh_

 _Battle! You wanna win it_

 _Let's have a battle, battle of the bands_

 _Let's have a battle, we'll go all in it_

 _Let's have a battle, battle, battle_

 _Battle of the bands_

 _Battle!_

"I can beat you!" A student said pointing at another.

 _Battle!_

"Ha! You wish!" She replied.

 _Battle!_

"I so want this!" Trixie said.

 _Battle!_

"Not if I get it first!" Another replied.

 _Me and you, you and me_

 _Why don't we see who is better?_

 _We don't have to be one and the same thing_

 _Oh, what's so wrong with a little competition?_

 _I'm going up and winning the audition_

The girls began to notice some friction happening between the students.

Sunset however, noticed the sparkling mist on the ground, coming out of the students, 'That can't be good.'

 _Battle! We wanna win it_

 _Let's have a battle, battle of the bands_

 _Let's have a battle, we'll go all in it_

 _Let's have a battle, battle, battle_

 _Battle of the bands!_

All the students began arguing with each other.

"Oooh. They're that kind of off." Pinkie said.

After that, the school bell rang, signalling everyone was to report to their classrooms.

But then Principal Celestia's voice spoke up, "Rainbow Dash, Sunset Shimmer, Applejack, Pinkie Pie, Fluttershy, and Rarity please report to the front of the school. Immediately."

"Huh?" The girls said looking at one another. They then dashed off towards the front of the school.

Adagio, Aria, and Sonata were too busy absorbing all the negative energy from the students.

But then something caught their attention. A huge amount of Chaos and Equestrian energy just surged in the area.

"Did you two just feel that?" Sonata asked.

"Yeah, that is a lot of Chaos Equestrian magic." Adagio said.

"But where is it coming from?" Aria asked.

"Hmm… Perhaps we should, _ask_ , around about the past events here." Adagio said looking at the students under their spell.

 **(Front of the school)**

The girls each saw Principal Celestia and Vice Principal Luna standing over something.

"We came as quickly as we could." Sunset said.

"What is it you needed us for?" Fluttershy asked.

"You said we weren't expecting any visitors. Right?" Luna asked.

"Yeah, why?" Rainbow said trying to see what the two sisters were standing over.

"Then please explain this." Celestia said moving out of the way, showing the Red Chaos Emerald glowing in the ground.

The girls gasped.

"A Chaos Emerald!?" Rainbow said, "But how is this possible? Sonic and his friends went back to Mobius with the Emeralds."

"I do not know. We don't dare touch it knowing what happened to students last year." Luna said.

Applejack went to pick it up, but the moment her hand touched it, she was blasted away by a shockwave.

"Whoa. What the hay was that?" Applejack asked.

Sunset looked at them emerald closely, then she saw it. The red lightning bolt crystal inside it, "That's an Element of Harmony inside the Chaos Emerald!"

"What's an element of harmony?" Rainbow asked.

"It's the same thing as the Element that was embedded in Twilight's crown." Sunset said, "A magical element representing a form of Friendship. But what is it doing in a Chaos Emerald, nevermind here?"

"I may know a little bit about that." A female voice asked.

They all turned and gasped.

Twilight Sparkle was standing behind the girls, along with Spike.

"Twilight!" The girls said running over to the purple teen.

They all join together in a group hug.

"What are you doing here, darling?" Rarity asked.

"I was about to explain that." Twilight said. She pointed at the Chaos Emerald, "I was going to go get book, when all of a sudden, six of the Chaos Emeralds in appeared in the library."

"Wait, they just appeared?" Sunset asked, "No Mobians were there?"

"Yeah. And then they flew off through the castle…" Twilight was saying, but was cut off by Rarity grabbing her tightly.

"Castle! You have a castle!?" Rarity squealed.

"Umm Rarity, more important stuff." Rainbow said.

"Oh. Right sorry." Rarity said backing away from Twilight.

"As I was saying, they began to fly around the castle, until they got to the vault." Twilight said, "Except the only things I kept in there was the Elements of Harmony. Princess Celestia and Princess Luna helped me protect it with a spell that only an Alicorn should be able to open."

"Ok. That doesn't explain much still." Applejack said.

"I wasn't done." Twilight said bluntly, "The Emeralds then passed through the vault door like it was _nothing_. I quickly opened the vault, only to see the Chaos Emeralds and Elements merge with one another. Even mine. Then they flew off again, and flew through the mirror into here."

"So you're saying that the Chaos Emeralds appeared out of nowhere, merged with your 'elements', then flew through the portal, and ended up on the front lawn of the school?" Rainbow asked.

"Yeah, pretty much." Twilight said.

"Then I have one question. Why can't we pick it up?" Applejack said.

"What do you mean?" Twilight said going to reach out for the emerald.

"Twilight! NO!" They shouted.

Too late, Twilight grabbed the emerald, and she was blasted back by the shock wave, "Ahg!"

"Hehe. Let me try!" Pinkie said going to grab the emerald. She was blasted back as well, "Weeeheeee!"

Sunset helped the two back up, "Yeah everytime we go to touch it, that happens."

Twilight looked at the Chaos Emerald, then saw the Element of Loyalty in it, "That's probably why."

"What?" Sunset asked.

"The emerald might now be linked to the element that is inside it." Twilight said, "The red emerald is linked to the Element of Loyalty. In Equestria, Rainbow Dash is the representative of Loyalty. Maybe Rainbow Dash is the one who needs to take this emerald."

"Are you sure? I personally don't want to go across the yard." Rainbow said.

"It's only a theory." Twilight said, "But I'm 90% sure I'm right."

"Ok then. If not, you owe me a game of one on one soccer." Rainbow said.

Twilight nodded.

Rainbow turned to the emerald, "Please be right." She reached out to grab the emerald.

"Please be right." Twilight said at the thought of one on one with Rainbow Dash.

Rainbow's hand made contact with the glassy surface of the emerald, and she was able to pull it out of the ground. The emerald glowed brightly in her hand. Then the element of harmony popped out of them emerald, and began floating around Rainbow.

"Um, Twilight?" Rainbow asked looking at the girl.

Twilight only stared in confusion.

The element then stopped at Rainbow's wrist, where her Chaos Element was. The two elements then switched places,

"What the?" Rainbow said watching the Chaos Element be replaced by the Element of Harmony.

The Chaos Element then returned into the Chaos Emerald, where it originally came from.

"What just happened?" Rainbow asked.

"I think your Chaos Element was just replaced with the Loyalty element." Twilight said looking at the Chaos Emerald.

"Wait does that mean?" Rainbow said trying to activate her transformation. But nothing happened, "NO!" Rainbow screamed in horror.

"Well that's not good." Pinkie said scratching her head.

"Well that's just great, I can't use my powers anymore and I've lost my awesome ninja outfit." Rainbow pouted as she crossed her arms.

"Ok so now then, if any of you find another Chaos Emerald, DO NOT touch it." Twilight said.

"What do we do then?" Fluttershy asked.

"Just leave it until we find a way to remove it safely." Twilight said.

They all nodded.

"God damn you stupid emerald." Rainbow said putting the red emerald into her pocket.

Little did any of the girls notice the three figures watching them from the shadows.

"I sense chaos energy coming from that strange gem that girl has." Aria said.

"I sense that all them have Equestrian magic in them, particularly the purple girl and that Sunset Shimmer person." Adagio said.

"So how do we plan to take it from them?" Sonata asked.

"Duh, like we always do." Aria said, "Cause a friction between them, and feed off their magic."

"Well that's not going to be easy. They seem to be protected by some kind of magic of their own." Adagio said, "They would have fallen under our spell if they weren't."

"We need to get stronger than that spell then." Aria said.

"How about we find one of those emeralds? I heard them say something about there being more than one." Sonata said.

Both Aria and Adagio just stared at the girl.

"What?" Sonata asked.

"You're not as stupid as you look apparently." Aria said.

"Hey, what's supposed to mean?" Sonata said crossing her arms.

"Then its settled, we need one of those emeralds." Adagio said, "After school, follow those girls and see if you can find one."

They nodded.

Adagio smiled evilly at the girls, "You are all in for a surprise. Not just a battle of bands, but a Chaotic one."

 **Darkmaster0224:** And that's chapter 2! Take it away bro!

 **CosmicAlchemist:** So, the Sunset Shimmer has strange suspicions about the Dazzlings. What are they really here for? Now the musical showcase has been turned into a battle of bands. And the girls have found one of the Chaos Emeralds, with an _element of harmony_ in it. Rainbow has lost her Chaos Element and powers. What are they in store for now? Are the Chaos Emeralds the only things that have showed up? What will this battle of bands be like? Find out next time.

 **Both:** Until next time. PEACEOUT!


End file.
